The present invention relates to guided air vehicles with control surfaces, in general, and more particularly, to method and apparatus for stowing and deploying the control surfaces of the guided air vehicle.
Guided air vehicles such as missiles, smart bombs, smart munitions, projectiles and bullets, for example, utilize control surfaces, such as fins, canards and wings, for example, to guide their trajectory along a desired flight path. Such air vehicles, especially those launched from manned or unmanned aircraft or ground craft, require that their control surfaces be stowed within or partially within the body of the air vehicle during storage and transportation, and also during launch in order to: (1) minimize potential damage; (2) allow the air vehicle to fit physically in the launch apparatus; and (3) minimize the effects of aerodynamic forces acting upon the control surfaces during launch. Once the air vehicle is in flight, the control surfaces may be deployed to their desired positions for guiding the vehicle. In many instances, control surface deployment is controlled by an on-board processor to allow completion of the air vehicle mission in accordance with a desired target strategy.
Many different apparatus have been developed for stowing and deploying the control surfaces of an air vehicle including: electromechanical, solenoids, pyrotechnic gas generators and retractors, and mechanical apparatus such as no-backs and inefficient transmissions, for example. Depending upon the circumstances and operating environments, some apparatus were found to be inappropriate for the given task; others were found not to work; and still others were found to be too expensive to implement. In addition, deployment apparatus using pyrotechnic devices or other similar devices have significant drawbacks of: not being indestructibly testable since they operate on a single shot basis, and of inducing significant shock to the supporting structure.
Accordingly, there is a need for method and apparatus for stowing and deploying control surfaces of a guided air vehicle that overcome the drawbacks and limitations of the conventional apparatus and are simpler and more cost effective. The present invention is intended to provide such apparatus and method that satisfy these needs.